Happy Presidents Day! I’m assuming this school was talking about the holiday honoring ALL of the U.S. Presidents and not just one President. Remember, with apostrophes you start with the correct word–in this case, “Presidents” because you’re talking about all the Presidents–and then make it possessive by adding an apostrophe (and an “s” if necessary). NOTE: various sources disagree about whether the apostrophe belongs at all. Since the apostrophe denotes possession and the holiday is to honor U.S. Presidents and not a day that belongs to those Presidents, no apostrophe is probably more correct. In any event, this school sign is obviously incorrect.
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